Smallpox

These went extinct in the wild before the modern anti-vaxxers could organize conservation efforts.

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“”Upon the principle of self-defense, of paramount necessity, a community has the right to protect itself against an epidemic of disease which threatens the safety of its members.

—U.S. Supreme Court giving the justification for mandatory smallpox vaccinations in 1905

Smallpox, also known as variola, was an infectious disease caused by the variola virus, a member of the Poxviridae family, and characterized by high fever and aches with subsequent widespread eruption of pimples that blister and pustulate. The eruptions scab over and leave scar tissue behind. It gets its name to distinguish it from the "great pox", today known as syphilis.

Smallpox came in two forms. The least dangerous was called variola minor or alastrim, which produced a relatively mild infection and had a death rate of approximately one percent. The more serious form of smallpox was called variola major, which can present in several ways. The most common presentation of variola major was called classic ordinary smallpox where a patient endured the symptoms listed above. Other, more serious presentations of smallpox included flat smallpox and hemorrhagic smallpox where the victim bled excessively rather than forming pustules. Flat and hemorrhagic pox were usually fatal, though as a whole variola major had a mortality rate of approximately 30%.

The disease was declared to have been eradicated in 1980, following centuries of inoculation efforts. The eradication of smallpox is often considered one of the greatest achievements in public health.

History

Portrait of Ferdinando II de' Medici (1626)

Though the exact origins of smallpox are unknown, variola major likely jumped species from cows or other domesticated animals at least 3000 years ago. Because smallpox would have required sustained contact with domestic animals and a certain level of population density, the likeliest sites for its origin would have been the locations of concentrated agricultural settlements in Asia or Africa, c. 10,000 BCE. Pharaoh Ramses V, who died in 1157 BCE, is believed to have died from smallpox.

Europeans have had smallpox epidemics with mortality rates ranging from 20-98%. Native Americans, who had no initial immunity, had mortality rates as high as 94%.

Smallpox blankets

It has often been alleged that smallpox was used by colonists to commit genocide on Native Americans using blankets from a smallpox ward, but it has been shown that smallpox is only communicated by person-to-person inhalation. There were, however, local incidents of Europeans intentionally infecting Native Americans with smallpox, and the initial spread of smallpox among Native American populations was devastating.

Inoculation and vaccination

A physician inspects the growth of cowpox on a milking maid, c. 1800

Connecting the survival of smallpox infection and immunity, the practice of inoculation began to be exercised during the 18^th century, although the practice of variolation (exposing a person to a small amount of the virus by inhalation or by scratching the skin) can be found dating back to 1000 CE in India, Western Asia, and China. In 1706, an enslaved African named Onesimus informed Cotton Mather, his slave owner in Massachusetts, about the method of variolation for smallpox that he had received when he lived in Africa. Mather later convinced a physician, Zabdiel Boylston, to conduct a variolation experiment during a 1721 smallpox outbreak in Boston. Mather and Boylston then used a statistical analysis to demonstrate the efficacy of variolation at preventing smallpox deaths: the fatality rate among non-variolated people who contracted smallpox was 14% vs. variolated people at 2%.

Vaccine

Smallpox vaccine kit, 1920s

In 1796, observing that individuals who contract cowpox become immune from smallpox, Edward Jenner, a British physician, inoculated a young boy with cowpox and then challenged his immune system with smallpox. Although a challenge trial with a potentially fatal disease would be considered unethical by modern standards, Jenner was correct in his observation. Jenner was not the first person to vaccinate with cowpox; it was being used in Europe for decades years prior. Jenner himself was inoculated with smallpox as a boy of 8 in 1757. Jenner's test on a single boy was not even the first experiment with cowpox vaccination. What Jenner can rightfully be credited for, though, is the relentless promotion of vaccination to prevent smallpox, and thereby changing how medicine was practiced. Many people were involved in the development and promotion of smallpox vaccination, and Jenner serves as an example of how often the so-called "great man theory" is fallacious.

The smallpox vaccine is manufactured from the vaccinia (cowpox) virus, and is the best available protection against smallpox infection, although there have recently been attempts to develop anti-viral medications. The smallpox vaccine is not without its issues. Because it is a live-virus vaccine, it cannot be administered to individuals who are immuno-compromised, or women who are pregnant or breastfeeding. The vaccine also causes severe reactions in people who have ever had any type of skin condition, particularly eczema. In all, the vaccine has a severe complication rate of 1 in 1000 (0.1%), with side effects ranging up to death in approximately 1 case per million (0.0001%). By contrast, the disease itself had a mortality rate of about 30% a significant portion of the infected people will infect other people, while vaccinated individuals do not transmit the disease. And yet some people still say the vaccine wasn't necessary and shouldn't have been used.

Eradication

“”It is now too manifest to admit of controversy, that the annihilation of smallpox — the dreadful scourge of the human race — will be the final result of vaccination.

—Edward Jenner in 1801

Jenner predicted shortly after his initial trial vaccination that smallpox would eventually be eliminated as a threat to humanity. Although many western nations had achieved mandatory vaccination programs, other countries could not afford the expense. As early as 1958, the Soviet Union called for the eradication of smallpox by a volunteer effort. Beginning in 1967, the World Health Organization began a worldwide vaccination campaign with the purpose of eradicating smallpox. The last natural case of variola major occurred in 1975, and the last natural case of variola minor in 1977.

The post-smallpox era

Following the eradication of smallpox, an accident occurred in 1978 resulting in the death of a British journalist. Based on this accident, all samples outside the control of the CDC, and the Soviet Ministry of Health were ordered destroyed. Despite subsequent calls for the destruction of the US and Russian stocks, they are still kept as the last remaining official stocks of smallpox samples.

Despite the existence of these official stocks, defectors from the former Soviet Union have alleged that the Soviet military commissioned the development of smallpox as a biological weapon from the 1970s to 1990s.

Conspiracy theories that smallpox might still exist in stocks outside of the former Soviet Union and the USA led to mainstream media dealing with the plans "in case of smallpox outbreak" during the Iraq War. Ultimately Saddam Hussein's smallpox were as hard to find as his other weapons of mass destruction.

Gallery

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  The mummy of Ramses V, showing evidence of pox scarring

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  Anti-smallpox vaccination cartoon from 1802

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  Stages of pox eruptions from smallpox infection

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  Sheetala (शीतला), the Hindu goddess believed to cure smallpox and other diseases

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  Hogu-byeolseong, the Korean smallpox goddess

See also

• Anti-vaccination movement
• Rabies